Rapid bedside testing for septic arthritis: evaluating cost-effective diagnostic tools

Abstract

Introduction: Diagnosing septic arthritis through synovial fluid culture and analysis can be time-consuming, and the limited accessibility of these tests in primary and secondary healthcare centers restricts their utility in emergency situations. Therefore, there is a pressing need for an alternative, rapid, and reliable test to significantly reduce morbidity. This study aimed to evaluate the efficacy of leucocyte esterase (LE) and glucose reagent strip tests for the early diagnosis of septic arthritis.

Methodology: This cross-sectional study included 75 individuals presenting with atraumatic native joint effusion. Following arthrocentesis, bedside LE and glucose strip testing were performed, along with synovial fluid culture and analysis.

Results: Out of the 75 cases, 25 (33.3%) were diagnosed with septic arthritis based on standard diagnostic tests. The LE strip test showed a sensitivity of 92%, specificity of 70%, positive predictive value (PPV) of 60%, and negative predictive value (NPV) of 94%. The glucose strip test demonstrated a sensitivity of 88%, specificity of 76%, PPV of 67%, and NPV of 93%. Combining the two tests resulted in a sensitivity of 84%, specificity of 88%, PPV of 77.8%, and NPV of 91.7%. The overall diagnostic accuracy was 80% for the glucose strip test, 77.3% for the LE strip test, and 86.7% for the combined results.

Conclusions: The LE and glucose strip tests are cost-effective bedside assessments for the rapid diagnosis of septic arthritis. Combining the results from both strip tests yielded greater diagnostic accuracy than each one alone.

Keywords: diagnostic accuracy; glucose; leucocyte esterase; septic arthritis; strip tests.